Some aircraft utilize inlet barrier filters (IBFs) associated with engine air inlets to filter particulate matter from air fed to the engine. In some cases, installation of an IBF requires utilization of aircraft performance charts that assume the filter media of the inlet barrier filters are clogged to a maximum allowable point without requiring opening of an inlet bypass door of the IBF. As such, utilization of the above-described aircraft performance and prescribes reduced aircraft performance. Alternatively, such accounting of reduced engine performance may take place in an engine power assurance check procedure, which attempts to minimize the reduction of aircraft performance. In cases where an engine fails to meet the minimum performance as judged by use of the above-described aircraft power performance charts, some power assurance check procedures require aborting a mission or changing mission capability expectations.